WASHINGTON — Thousands of people, many holding signs with names of gun violence victims and messages such as ‘‘Ban Assault Weapons Now,’’ joined a rally for gun control Saturday, marching from the Capitol to the Washington Monument.

Leading the crowd were marchers with ‘‘We Are Sandy Hook’’ signs, paying tribute to victims of the December school shooting in Newtown, Conn. Washington Mayor Vincent Gray and other city leader marched alongside. The crowd stretched for at least two blocks on Constitution Avenue.

Participant Kara Baekey from Norwalk, Conn., said that when she heard about the Newtown shooting, she immediately thought of her two young children. She said she decided she must take action, and that’s why she traveled to Washington for the march.

‘‘I wanted to make sure this never happens at my kids’ school or any other school,’’ Baekey said. ‘‘It just can’t happen again.’’

Once the crowd arrived at the monument, speakers called for a ban on military-style assault weapons and high-capacity ammunition and for universal background checks on gun sales.

Education Secretary Arne Duncan told the crowd it is not about taking away Second Amendment gun rights, but about gun safety and saving lives. He said he and President Obama would do all they could to enact gun control policies.

‘‘This is about trying to create a climate in which our children can grow up free of fear,’’ Duncan said. ‘‘This march is a starting point
.’’

Eleanor Holmes Norton, D.C.’s nonvoting representative in Congress, said the gun lobby can be stopped, and the crowd chanted back, ‘‘Yes, we can.’’

‘‘We are all culpable if we do nothing now,’’ Norton said

James Agenbroad, 78, of Garrett Park, Md., carried a handwritten cardboard sign that read ‘‘Repeal the 2nd Amendment.’’ He called it the only way to stop mass killings because he thinks the Supreme Court will strike down any other restrictions on guns.

‘‘You can repeal it,’’ he said. ‘‘We repealed Prohibition.’’

Molly Smith, the artistic director of Washington’s Arena Stage, organized the march. Organizers said that in addition to 100 people from Newtown, participants came from New Jersey, New York, and Philadelphia. Others flew in from Seattle, San Francisco, and Alaska.

The march organizers support Obama’s call for gun control measures.

‘‘With the drum roll, the consistency of the mass murders, and the shock of it, it is always something that is moving and devastating to me. And then, it’s as if I move on,’’ Smith said. ‘‘And in this moment, I can’t move on. I can’t move on.

‘‘I think it’s because it was children, babies,’’ she said. ‘‘I was horrified by it.’’

After the Connecticut shootings, Smith began organizing. The group One Million Moms for Gun Control, the Washington National Cathedral, and two other churches signed on to cosponsor the march. Organizers have raised more than $50,000 to pay for equipment and fees, Smith said.

Lawmakers from the District of Columbia and Maryland rallied the crowd, along with Marian Wright Edelman of the Children’s Defense Fund and Colin Goddard, a Virginia Tech massacre survivor.

Goddard said he was shot four times at Virginia Tech and is motivated to keep fighting for gun control because what happened to him keeps happening — and nothing’s been done to stop it.

‘‘We are Americans,’’ he said, drawing big cheers. ‘‘We have overcome difficulties when we realize we are better than this.’’